Ben Stiller and Christine Taylor attend the 25th anniversary of Project ALS in NYC.Photo:Jamie McCarthy/Getty

Ben Stiller, Christine Taylor, attend the Project ALS 25th Anniversary Gala at Jazz at Lincoln Center on October 26, 2023 in New York City.

Jamie McCarthy/Getty

Ben Stillerand wifeChristine Taylormade a rare public appearance with their 18-year-old sonQuinlin DempseyThursday for a cause dear to the family.

Her friends were on-hand to celebrate Project ALS’s 25th anniversary, held at Jazz at Lincoln Center, Stiller told PEOPLE.

“All the people who are part of Project ALS go that far back with her,” Stiller told PEOPLE. “Everyone’s here on a personal level.”

Ben Stiller and Jennifer Estess in 1999.Evan Agostini/Liaison

Comedian Ben Stiller and Jennifer Estes attend the Project A. L. S. “Tomorrow is Tonight” Benefit Gala September 27, 1999 in New York City. Project A.L.S. is a non-profit organization that raises awareness for ALS (amyotrophic lateral sclerosis) and funds ALS research worldwide.

Evan Agostini/Liaison

ALS — oramyotrophic lateral sclerosis— is a fatal, progressive nervous system disease, affecting nerve cells in the brain and spinal cord, according to theMayo Clinic.

Often called Lou Gehrig’s disease, after the baseball star who was diagnosed with it in 1939, ALS “often begins with muscle twitching and weakness in an arm or leg, trouble swallowing or slurred speech,” the Mayo Clinic explains.

Estess was first diagnosed with the disease in 1997, according to theProject ALS.site, which said that her doctor told her to “max out her credit cards and eat junk food.”

Instead, she founded Project ALS, which has since raised more than $90 million to fund its search for a cure.

Stiller praised Project ALS, telling PEOPLE it’s an “amazingly effective organization.”

“It’s hard to deal with because [there’s] not a lot of hope for people, when there isn’t actually a cure. But what Project ALS has done is created hope,” Stiller told PEOPLE.

He added that the foundation has “worked so hard to get money to get funding for the research and they’re making real progress. So that’s what it’s about.”

The cause of the disease is unknown, and 90% of cases occur without any known history or genetic cause, according to theALS Association. Most people who develop ALS are between the ages of 40 and 70, with an average age of 55 at the time of diagnosis, but there are cases of ALS in people in their twenties and thirties. Men are 20% more likely than women to be diagnosed, although the incidence is more equal as age increases.

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source: people.com